Image processing systems in which multi function peripherals (MFPs) having Web browsers incorporated therein are capable of communicating with Web servers over networks are widely known. In such an image processing system, the MFP receives screen information that is provided by the Web server and that is described in, for example, Hypertext Markup Language (HTML) to display an operation screen used for operating the MFP. The MFP can receive various operations from a user with the operation screen. It is not necessary for the MFP to hold all the screen information used for displaying the operation screen of the MFP and it is possible to easily customize the operation screen from the Web server.
In addition, Japanese Patent Laid-Open No. 2007-042098 discloses a case in which an error (for example, paper jam in a printer) occurs while a job is being executed in an MFP that executes the job in response to a request for a Web service from an external server. According to the technology in PTL 1, the MFP notifies the external server of the error if the above error occurs. The MFP acquires screen information transmitted from the external server to display an appropriate error screen. The above processing allows the Web server to easily customize, for example, a screen for indicating the content of the error and a screen for guiding a process to return from the error.
However, the configuration of the image processing system disclosed in Japanese Patent Laid-Open No. 2007-042098 has the following problems. For example, if the above error occurs while a job is being executed, the MFP notifies the external server of the occurrence of the error (or requests an error screen from the external server) and waits for a response from the external server according to the technology in Japanese Patent Laid-Open No. 2007-042098. A time lag occurs in this process because the screen information on the error screen is acquired from the external server through the Web server and a network after the error has occurred to display the error screen. The user cannot know that the error has occurred during the time lag.
Configuring the MFP so that the screen information on the error screen is held by the MFP and displaying the error screen on the basis of the screen information held by the MFP if an error occurs cause no time lag to occur. However, it is not possible for the external apparatus to customize the error screen in this case.
Similar problems generally occur not only for the error screen but also for a case in which the state of a job executed by an image processing apparatus is changed. Specifically, it is not possible for the user to know the change in the state of the job at least since the processing state of the job has been changed before a screen based on the screen information received from the external apparatus is displayed.
In order to resolve the above problems, it is an object of the present invention to provide a mechanism capable of rapidly notifying the user of a change in the state of a job.